This disclosure relates generally to a bus bar and, more particularly, to a multilayered bus bar. Many electrical systems utilize bus bars. For example, electrified vehicles may include a bus bar to exchange power with a battery that stores electrical power.
Generally, electric vehicles differ from conventional motor vehicles because electric vehicles selectively drive the vehicle using one or more battery-powered electric machines. Conventional motor vehicles, by contrast, rely exclusively on an internal combustion engine to drive the vehicle. Electric vehicles may use electric machines instead of, or in addition to, to the internal combustion engine. Example electric vehicles include hybrid electric vehicles (HEV's), plug in hybrid electric vehicles (PHEV's), and battery electric vehicles (BEV's).
Referring to a prior art FIG. 1, a power train of an example prior art electric vehicle can include a power converter system utilizing at least one bus bar 200 that exchanges electricity. The prior art bus bar 200 is greatly simplified in this example. The prior art bus bar 200 has two layers. One layer is positive and the other layer is negative. In the power converter systems of electric vehicles, the prior art bus bar 200 can have a relatively high AC resistance due to the skin effect and the proximity effect associated with high frequency switching. This can lead to power loss and undesirably high thermal energy levels.
Prior art FIG. 2 shows a plot 210 associated with the prior art bus bar 200. The plot 210 shows a first trace 220a of parasitic inductance verses frequency, and a second trace 220b of parasitic resistance verses frequency for the prior art bus bar 200. The frequency range in this plot 210 is from 0 to 100 kilohertz. As known, relatively high level of parasitic inductance and parasitic resistance are typically undesirable because the parasitic resistance causes extra power losses as described in the previous paragraph and the parasitic inductance can cause voltage spikes associated with power semiconductor device switching actions and lead to relatively poor utilization of the power semiconductor device rated voltage due to a relatively large required voltage margin.